Optical fiber connection system including optical fiber alignment device

ABSTRACT

The present disclosure relates to an optical fiber alignment device that has an alignment housing that includes first and second ends. The alignment housing defines a fiber insertion axis that extends through the alignment housing between the first and second ends. The alignment housing includes a fiber alignment region at an intermediate location between the first and second ends. First and second fiber alignment rods are positioned within the alignment housing. The first and second fiber alignment rods cooperate to define a fiber alignment groove that extends along the fiber insertion axis. The first and second fiber alignment rods each having rounded ends positioned at the first and second ends of the alignment housing.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.15/980,170, filed 15 May 2018, now U.S. Pat. No. 10,564,369, which is aContinuation of U.S. application Ser. No. 15/403,644, filed 11 Jan.2017, now U.S. Pat. No. 10,001,605, issued 19 Jun. 2018, which is aContinuation of U.S. application Ser. No. 14/377,189, filed 7 Aug. 2014,now U.S. Pat. No. 9,575,263, issued 21 Feb. 2017, which is a NationalStage Application of PCT/EP2013/052345, filed 6 Feb. 2013, which claimsbenefit of U.S. Application No. 61/596,035, filed 7 Feb. 2012 and U.S.Application No. 61/758,021, filed 29 Jan. 2013 and which applicationsare incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to optical fiber connection systems andto devices and methods for aligning two fibers end-to-end.

BACKGROUND

Modern optical devices and optical communications systems widely usefiber optic cables. Optical fibers are strands of glass fiber processedso that light beams transmitted through the glass fiber are subject tototal internal reflection wherein a large fraction of the incidentintensity of light directed into the fiber is received at the other endof the fiber.

Many approaches to achieve fiber alignment can be found in the priorart, among them are V-grooves and ferrules. Ferrule based alignmentsystems including include ferruled connectors which use cylindricalplugs (referred to as ferrules) that fit within an alignment sleeve(e.g., a cylindrical split sleeve with elastic characteristics) toperform fiber alignment. Precision holes are drilled or molded throughthe centers of the ferrules. Optical fibers are secured (e.g., potted)within the precision holes with polished ends of the optical fiberslocated at end faces of the ferrules. Precise fiber alignment depends onthe accuracy of the central hole of each ferrule. Fiber alignment occurswhen two ferrules are inserted into an alignment sleeve such that theend faces of the ferrules oppose one another and the optical fiberssupported by the ferrules are co-axially aligned with one another.Normally, ferruled connectors use ceramic or metal ferrules in which theprecision center holes are drilled. Disadvantageously, drilling of sucha central hole that is accurate enough for aligning can be difficult. Inaddition, a connector containing a ferrule has very high manufacturingcosts. Therefore looking for adequate alignment solutions containingferrule-less connectors would be more desirable.

V-grooves are commonly used in prior-art ferrule-less fiber opticalignment devices. An example is the V-groove method described in U.S.Pat. No. 6,516,131 used for alignment of optical fiber ends. TheV-groove is uni-directionally or bi-directionally tapered for enablingeasy positioning of the fibers. Optical fibers are pressed into theV-grooves and line contact between the optical fibers and the surfacesof the V-grooves assists in providing precise alignment of the opticalfibers. In one example, two optical fibers desired to be opticallyconnected together are positioned end-to-end within a V-groove such thatthe V-groove functions to co-axially align the optical fibers. End facesof the aligned optical fibers can abut one another.

SUMMARY

One aspect of the present disclosure relates to a device and method foraligning two fibers end-to-end. Co-axial alignment can be providedbetween the optical fibers of two fiber optic connectors so as toprovide an optical coupling between the optical fibers. In such anembodiment, the optical connectors can be ferrule-less opticalconnectors. Co-axial alignment can also be provided between the end ofan optical fiber of a fiber optic cable and a stub end of an opticalfiber supported by a ferrule. In certain embodiments, fiber alignmentdevices in accordance with the principles of the present disclosure canaccurately align optical fiber while using a minimal number of parts toreduce cost and facilitate assembly.

The term “fiber” as used herein relates to a single, opticaltransmission element having a core usually having a diameter of 8-12 μmand a cladding usually having a diameter of 120-130 μm, wherein the coreis the central, light-transmitting region of the fiber, and the claddingis the material surrounding the core to form a guiding structure forlight propagation within the core. The core and cladding can be coatedwith a primary coating usually comprising one or more organic or polymerlayers surrounding the cladding to provide mechanical and environmentalprotection to the light-transmitting region. The primary coating mayhave a diameter ranging e.g. between 200 and 300 μm. The core, claddingand primary coating usually are coated with a secondary coating, aso-called “buffer”, a protective polymer layer without opticalproperties applied over the primary coating. The buffer or secondarycoating usually has a diameter ranging between 300-1100 μm, depending onthe cable manufacturer.

The term “light” as used herein relates to electromagnetic radiation,which comprises a part of the electromagnetic spectrum that isclassified by wavelength into infrared, the visible region, andultraviolet.

Index matching gel can be used with alignment devices in accordance withthe principles of the present disclosure to improve the opticalconnection between the open light transmission paths of the first andsecond optical fibers. The index matching gel preferably has an index ofrefraction that closely approximates that of an optical fiber is used toreduce Fresnel reflection at the surface of the bare optical fiber ends.Without the use of an index-matching material, Fresnel reflections willoccur at the smooth end faces of a fiber and reduce the efficiency ofthe optical connection and thus of the entire optical circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an optical fiber alignment device inaccordance with the principles of the present disclosure;

FIG. 2 is another perspective view of the optical fiber alignment deviceof FIG. 1;

FIG. 3 is a further perspective view of the optical fiber alignmentdevice of FIG. 1;

FIGS. 4-6 are exploded views of the optical fiber alignment device ofFIG. 1;

FIG. 7 is a cross-sectional view taken along section line 7-7 of FIG. 2;

FIG. 8 is a top view of the optical fiber alignment device of FIG. 1with a clip of the optical fiber alignment device removed;

FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 7with the clip removed;

FIG. 10 is an end view of the optical fiber alignment device of FIG. 1;

FIGS. 11 and 12 show a connector in which the optical fiber alignmentdevice of FIG. 1 has been incorporated;

FIG. 13 is a perspective view of a duplex fiber optic adapter in whichtwo optical fiber alignment devices of the type shown at FIG. 1 havebeen incorporated;

FIG. 14 is an end view of the duplex fiber optic adapter of FIG. 13;

FIG. 15 is a top view of the duplex fiber optic adapter of FIG. 13;

FIG. 16 is a cross-sectional view taken along section line 16-16 of FIG.15;

FIGS. 17 and 18 show a simplex fiber optic adapter in which one of theoptical fiber alignment devices of FIG. 1 has been incorporated;

FIG. 19 shows the simplex fiber optic adapter of FIGS. 17 and 18 withfiber optic connectors inserted therein;

FIG. 20 illustrates a fiber optic connector in a non-connected state;

FIG. 21 illustrates the fiber optic connector of FIG. 20 in a connectedstate;

FIG. 22 is a front, top, perspective view of the fiber optic connectorof FIG. 20 with a shutter of the fiber optic connector in a closedposition;

FIG. 23 is a front, bottom, perspective view of the fiber opticconnector of FIG. 22 with the shutter in the closed position;

FIG. 24 is a front, top, perspective view of the fiber optic connectorof FIG. 20 with a shutter of the fiber optic connector in an openposition;

FIG. 25 is a front, bottom, perspective view of the fiber opticconnector of FIG. 22 with the shutter in the open position;

FIG. 26 is a bottom view of a front end of the fiber optic connector ofFIG. 22 with a shutter latch mechanism in a latching position;

FIG. 27 is a bottom view of a front end of the fiber optic connector ofFIG. 22 with the shutter latch mechanism in a release position;

FIG. 28 is a perspective view of the shutter latch mechanism of thefiber optic connector of FIG. 22;

FIG. 29 shows the fiber optic adapter of FIG. 16 with a first fiberoptic connector loaded in the left port and second fiber optic connectoraligned with the right port;

FIG. 30 shows the fiber optic adapter of FIG. 29 with the second fiberoptic connector inserted to a position where the shutter latch mechanismhas been moved to a release position;

FIG. 31 shows the fiber optic adapter of FIG. 30 with the second fiberoptic connector inserted to a position where the shutter has pivotedpartially from the closed position toward the open position throughcontact with a shutter actuation post within the right port of the fiberoptic adapter;

FIG. 32 shows the fiber optic adapter of FIG. 31 with the first andsecond fiber optic connectors fully loaded and secured in the fiberoptic adapter and with optical fibers of the first and second fiberoptic connectors co-axially aligned by an alignment device within thefiber optic adapter;

FIG. 33 shows the fiber optic adapter of FIG. 32 with the second fiberoptic connector partially withdrawn from the right port of the fiberoptic adapter and with the shutter of the second fiber optic connectorcontacting a shutter actuation post within the right port of the fiberoptic adapter;

FIG. 34 shows the fiber optic adapter of FIG. 33 with the shutterpivoted to the closed position through contact with the shutteractuation post;

FIG. 35 is a cross-sectional view of the fiber optic adapter of FIG. 29with the second fiber optic connector inserted into the right port ofthe fiber optic adapter to a point where the shutter latch mechanism ofthe second fiber optic connector is initially engaging release rails ofthe fiber optic adapter and the shutter latch mechanism still in thelatching position of FIG. 26;

FIG. 36 is a cross-sectional view of the fiber optic adapter of FIG. 29with the second fiber optic connector inserted into the right port ofthe fiber optic adapter to a point where the shutter latch mechanism ofthe second fiber optic connector is engaging release rails of the fiberoptic adapter and the release rails are holding the shutter latchmechanism in the release position of FIG. 27;

FIG. 37 is an exploded view showing a fiber optic adapter and aconverter for converting the fiber optic connector of FIG. 20 to aferruled fiber optic connector;

FIG. 38 is an exploded view of the converter of FIG. 37;

FIG. 39 is an assembled view of the converter of FIG. 38;

FIG. 40 is a cross-sectional view of the converter of FIG. 39;

FIG. 41 is a cross-sectional view of the converter of FIG. 39 with thefiber optic connector of FIG. 20 inserted therein;

FIG. 42 shows an alternative mounting configuration for mounting a fiberalignment device to a ferrule assembly;

FIG. 43 is a perspective view of another optical fiber alignment devicein accordance with the principles of the present disclosure;

FIG. 44 is another perspective view of the optical fiber alignmentdevice of FIG. 43;

FIG. 45 is a further perspective view of the optical fiber alignmentdevice of FIG. 43;

FIG. 46 is a side view of the optical fiber alignment device of FIG. 43;

FIG. 47 is a top view of the optical fiber alignment device of FIG. 43;

FIG. 48 is a first end view of the optical fiber alignment device ofFIG. 43;

FIG. 49 is a second end view of the optical fiber alignment device ofFIG. 43;

FIG. 50 is a longitudinal cross-sectional view of the optical fiberalignment device of FIG. 48 taken along section line 50-50;

FIG. 51 is a longitudinal cross-sectional view of FIG. 50 with theinternal components removed;

FIG. 52 is an exploded view of the optical fiber alignment device ofFIG. 43; and

FIG. 53 is a transverse cross-sectional view of the optical fiberalignment device of FIG. 47 taken along section line 53-53.

DETAILED DESCRIPTION

FIGS. 1-10 illustrate an optical fiber alignment device 20 in accordancewith the principles of the present disclosure. The optical fiberalignment device 20 is used to coaxially align and optically connecttogether two optical fibers such that optical transmissions can beconveyed from optical fiber to optical fiber. When first and secondoptical fibers are inserted into opposite ends of the optical fiberalignment device 20 along a fiber insertion axis 22, the optical fibersare guided to an orientation in which the optical fibers are coaxiallyaligned with one another with end faces of the optical fibers abuttingor in close proximity to one another. A mechanism can be provided withinthe optical fiber alignment device 20 for mechanically retaining theoptical fibers in an optically connected orientation. Thus, the opticalfiber alignment device 20 functions to provide a mechanical splicebetween the optical fibers inserted therein. In certain embodiments, anindex matching gel can be provided within the optical fiber alignmentdevice 20 for enhancing the optical coupling between the aligned opticalfibers retained within the optical fiber device 20.

Referring to FIGS. 1-10, the optical fiber alignment device 20 includesan alignment housing 24 (e.g., a molded plastic housing) including firstand second ends 26, 28. The alignment housing 24 defines a fiberinsertion axis 22 that extends through the alignment housing 24 betweenthe first and second ends 26, 28. As shown at FIG. 7, the alignmenthousing 24 includes a fiber alignment region 30 at an intermediatelocation between the first and second ends 26, 28. The fiber alignmentregion 30 includes an alignment groove 32 that extends along the fiberinsertion axis 22. The alignment housing 24 also defines a pocket 34 atthe fiber alignment region 30 adjacent to the alignment groove 32. Thefirst end of the alignment housing 26 includes a first funnel 36 thatextends along the fiber insertion axis 22 for guiding a first opticalfiber (e.g., see the left optical fiber 100 at FIG. 19) into the fiberalignment region 30. The second end 28 of the alignment housing 24includes a second funnel 38 that extends along the fiber insertion axis22 for guiding a second optical fiber (e.g., see the right optical fiber100 at FIG. 19) into the fiber alignment region 30. The first and secondfunnels 36, 38 are configured to taper inwardly toward the fiberinsertion axis 22 as the first and second funnels 36, 38 extend into thealignment housing 24 toward the fiber alignment region 30. The taperedconfiguration of the funnels 36, 38 functions to guide the first andsecond optical fibers into coaxial alignment with the fiber insertionaxis 22 such that the optical fibers can be easily slid intoregistration with the alignment groove 32.

When the first and second optical fibers are inserted into the alignmenthousing 24 along the fiber insertion axis 22, alignment between theoptical fibers is provided by the alignment groove 32. In certainembodiments, the alignment groove 32 can have a curved transversecross-sectional shape (e.g., a semi-circular transverse cross-sectionalshape as shown at FIG. 9) and can be configured to receive the opticalfibers therein such that the optical fibers seat within the alignmentgroove 32. In such an embodiment, it will be appreciated that thetransverse cross-sectional shape of the alignment groove 32 complementsthe outer diameters of the optical fibers. In alternative embodiments,the alignment groove can have a transverse cross-sectional shape that isgenerally v-shaped (i.e., the alignment groove 32 can be a v-groove). Insuch an embodiment, the v-groove provides two lines of contact with eachof the optical fibers inserted therein. In this way, the line/pointcontact with the v-groove assists in providing accurate alignment of theoptical fibers.

It will be appreciated that the optical fibers inserted within theoptical fiber alignment device 20 are preferably preprocessed. Forexample, in certain embodiments, coatings of the optical fibers can bestripped from end portions of the optical fiber such that bare glassportions of the optical fibers are inserted within the fiber alignmentregion 30. In such embodiments, the alignment groove 32 is configured toreceive the bare glass portions of the optical fibers. In oneembodiment, the bare glass portions can have diameters ranging from120-130 microns and can be formed by glass cladding layers that surroundglass cores.

The optical fiber alignment device 20 further includes structure forurging the optical fibers into contact with the fiber alignment groove32. In the depicted embodiment, the fiber optic alignment device 20includes first and second balls 40, 41 (i.e., fiber contact members)positioned within the pocket 34. The pocket 34 has an elongate directionthat extends along the fiber insertion axis 22 and the pocket 34functions to align the balls 40, 41 (e.g., spheres) along the fiberinsertion axis 22. The optical fiber alignment device 20 furtherincludes a biasing arrangement for urging the balls 40, 41 generallytoward the alignment groove 30. For example, the biasing arrangement canurge the balls 40, 41 in a direction transverse with respect to thefiber insertion axis 22. In the depicted embodiment, the biasingarrangement is shown including a clip 42 (e.g., a metal clip havingelastic properties) mounted (e.g., snap fitted) over the alignmenthousing 24 adjacent the fiber alignment region 30. The clip 42 has atransverse cross-sectional profile that is generally C-shaped. When theclip 42 is snapped over the alignment housing 24, the clip 42 functionsto capture the balls 40, 41 within the pocket 34. The clip 42 includesbiasing structures such as first and second springs 44, 45 forrespectively biasing the balls 40, 41 toward the alignment groove 32. Asdepicted, the springs 44, 45 are leaf springs having a cantileveredconfiguration with a base end integrally formed with a main body of theclip 42 and free ends that are not connected to the main body of theclip 42. In the depicted embodiment, the first spring 44 extends (e.g.,curves) from its base end to its free end in a generally clockwisedirection around the axis 22 and the second spring 45 extends (e.g.,curves) from its base end to its free end in a generallycounterclockwise direction around the axis 22. The springs 44, 45 aredefined by cutting or slitting the clip 42 so as to define slots in theclip 42 that surround three sides of each of the springs 44, 45.

FIGS. 11 and 12 show the optical fiber alignment device 20 incorporatedinto a fiber optic connector 50 such as an SC-connector. The connector50 includes a ferrule 52 supporting an optical fiber 54. A dust cap 56can be mounted over the interface end of the ferrule 52. The opticalfiber 54 includes a stub end 58 that projects rearwardly from theferrule 52 into the body of the connector 50. The stub end 58 isinserted within the first funnel 36 of the optical fiber alignmentdevice 20 and is shown pressed within the fiber alignment groove 32 bythe first ball 40. The connector 50 is optically connected to anotherfiber by inserting the fiber through the rear end of the connector 50and into the second funnel 38. As the optical fiber is inserted into thesecond funnel 38, the optical fiber is guided into alignment with thefiber insertion axis 22. Continued insertion of the optical fiber causesthe fiber to register with the fiber alignment groove 32 and displacethe second ball 41 against the bias of the corresponding second spring45. In this way, the spring biased balls 40, 41 assist in retaining theoptical fibers in alignment along the alignment groove 32. In oneembodiment, the connector 50 can have mechanical field splicecapabilities in which the connector can be field spliced to an opticalfiber by inserting the optical fiber through the rear end of theconnector 50 and into the fiber alignment device 20.

FIGS. 13-16 illustrate a duplex fiber optic adapter 60 adapted forreceiving and optically connecting two pairs of fiber optic connectors.In one embodiment, the connectors have an LP connector typeprofile/footprint. Two of the optical fiber alignment devices 20 aremounted within the duplex fiber optic adapter 60. When fiber opticconnectors are inserted within coaxially aligned ports 62 of the fiberoptic adapter 60, optical fibers of the fiber optic connectors enter theoptical fiber alignment device 20 through the first and second funnels36, 40 and are mechanically spliced at the fiber alignment region 30.

FIGS. 17 and 18 show simplex fiber optic adapters 64, 66 having the samebasic configuration as the duplex fiber optic adapter 60. The simplexfiber optic adapters 64, 66 are the same except the simplex adapter 66is provided with shutters 68. The shutters 68 flex open when fiber opticconnectors are inserted into corresponding ports of the adapter 66. Whenno connectors are inserted in the adapter 66, the shutter 68 inhibitsdust or other contaminants from entering the fiber alignment device 20within the interior of the adapter 66.

FIG. 19 shows the simplex fiber optic adapter 64 being used to opticallyand mechanically couple two fiber optic connectors 69. In one example,the fiber optic connectors 69 can have an LP-connector typefootprint/profile/shape. The fiber optic connectors 69 include latches70 (e.g., resilient cantilever style latches) that engage catches 71 ofthe fiber optic adapter 64. When the fiber optic connectors 69 areinserted within coaxially aligned ports of the fiber optic adapter 64,shutters 74 (see FIG. 20) of the fiber optic connectors 69 are retracted(see FIG. 21) thereby exposing ferrule-less free ends 100′ of theoptical fibers 100 of the fiber optic connectors 69. Continued insertionof the fiber optic connectors 69 into the ports of the fiber opticadapter 64 causes the end portions 100′ of the optical fibers 100 toenter the optical fiber alignment device 20 through the first and secondfunnels 36, 38. The optical fibers 100 slide along the insertion axis 22and are brought into registration with the fiber alignment groove 30. Asthe optical fibers 100 move along the fiber alignment groove 30, theoptical fibers 100 force their corresponding balls 40, 41 away from thealignment groove 32 against the bias of the springs 44, 45. The opticalfibers 100 slide along the alignment groove 32 until end faces of theoptical fibers 100 are optically coupled to one another. In thisconfiguration, the springs 44, 45 and the balls 40, 41 function to clampor otherwise retain the optical fibers 100 in the optically coupledorientation.

The embodiments disclosed herein can utilize a dimensionally recoverablearticle such as a heat-recoverable tube/sleeve for securing/lockingoptical fibers at desired locations within the connector bodies and forattaching cable jackets and cable strength members to the connectors. Adimensionally recoverable article is an article the dimensionalconfiguration of which may be made substantially to change whensubjected to treatment. Usually these articles recover towards anoriginal shape from which they have previously been deformed, but theterm “recoverable” as used herein, also includes an article which adoptsa new configuration even if it has not been previously deformed.

A typical form of a dimensionally recoverable article is aheat-recoverable article, the dimensional configuration of which may bechanged by subjecting the article to heat treatment. In their mostcommon form, such articles comprise a heat-shrinkable sleeve made from apolymeric material exhibiting the property of elastic or plastic memoryas described, for example, in U.S. Pat. No. 2,027,962 (Currie); U.S.Pat. No. 3,086,242 (Cook et al); and U.S. Pat. No. 3,597,372 (Cook), thedisclosures of which are incorporated herein by reference. The polymericmaterial has been cross-linked during the production process so as toenhance the desired dimensional recovery. One method of producing aheat-recoverable article comprises shaping the polymeric material intothe desired heat-stable form, subsequently crosslinking the polymericmaterial, heating the article to a temperature above the crystallinemelting point (or, for amorphous materials the softening point of thepolymer), deforming the article, and cooling the article while in thedeformed state so that the deformed state of the article is retained. Inuse, because the deformed state of the article is heat-unstable,application of heat will cause the article to assume its originalheat-stable shape.

In certain embodiments, the heat-recoverable article is a sleeve or atube that can include a longitudinal seam or can be seamless. In certainembodiments, the tube has a dual wall construction including an outer,heat-recoverable annular layer, and an inner annular adhesive layer. Incertain embodiments, the inner annular adhesive layer includes ahot-melt adhesive layer.

In one embodiment, the heat-recoverable tube is initially expanded froma normal, dimensionally stable diameter to a dimensionally heat unstablediameter that is larger than the normal diameter. The heat-recoverabletube is shape-set to the dimensionally heat unstable diameter. Thistypically occurs in a factory/manufacturing setting. The dimensionallyheat unstable diameter is sized to allow the heat-recoverable tube to beinserted over two components desired to be coupled together. Afterinsertion over the two components, the tube is heated thereby causingthe tube to shrink back toward the normal diameter such that the tuberadially compresses against the two components to secure the twocomponents together. The adhesive layer is preferably heat activatedduring heating of the tube.

According to one embodiment, the heat-recoverable tube may be formedfrom RPPM material that deforms to a dimensionally heat stable diametergenerally at around 80° C. RPPM is a flexible, heat-shrinkable dual walltubing with an integrally bonded meltable adhesive liner manufactured byRaychem. According to another embodiment, the heat-recoverable tube 56may be formed from HTAT material that deforms to a dimensionally heatstable diameter generally at around 110° C. HTAT is a semi-flexible,heat-shrinkable tubing with an integrally bonded meltable adhesive innerlining designed to provide moisture proof encapsulation for a range ofsubstrates, at elevated temperatures. HTAT is manufactured by Raychemfrom radiation cross-linked polyolefins. The inner wall is designed tomelt when heated and is forced into interstices by the shrinking of theouter wall, so that when cooled, the substrate is encapsulated by aprotective, moisture proof barrier. According to one embodiment, theheat-recoverable tube may have a 4/1 shrink ratio between thedimensionally heat unstable diameter and the normal dimensionally heatstable diameter.

Referring again to FIGS. 20 and 21, the fiber optic connector 69 is partof a fiber optic assembly that includes a fiber optic cable 112terminated to the fiber optic connector 69. The fiber optic cable 112includes the optical fiber 100, a buffer tube 117 (e.g., a buffer layerhaving an outer diameter ranging from 300-1100 microns) that surroundsthe optical fiber 100, an outer jacket 116 and a strength layer 118positioned between the buffer tube 117 and the outer jacket 116. Theoptical fiber 100 can also include a coating layer 113 that surrounds abare glass portion 111. In one example, the coating layer 113 can havean outer diameter ranging from 230-270 microns and the bare glassportion 111 can have a cladding layer having an outer diameter rangingfrom 120-130 microns and a core having a diameter ranging from 5-15microns. Other examples can have different dimensions. The strengthlayer 118 can provide tensile reinforcement to the cable 112 and caninclude strength members such as reinforcing aramid yarns. The fiberoptic connector 69 includes a main connector body 122 having a frontmating end 124 and a rear cable terminating end 126. An electricallyconductive (e.g., metal) rear insert 130 is secured (e.g., press fitwithin) the rear cable terminating end 126 of the connector body 122.The optical fiber 100 extends from the fiber optic cable 112 forwardlythrough the main connector body 122 and has a ferrule-less end portion100′ that is accessible at the front mating end 124 of the connectorbody 122. Adjacent the rear cable terminating end 126 of the connectorbody 122, the optical fiber 100 is fixed/anchored against axial movementrelative to the connector body 122. For example, the optical fiber 100can be secured to a fiber securement substrate 119 by a shaperecoverable article 121 (e.g., a heat shrink sleeve having an innerlayer of hot melt adhesive). The fiber securement substrate 119 can beanchored within the rear insert 130. The rear insert 130 can be heatedto transfer heat to the shape recoverable article thereby causing theshape recoverable article 121 to move from an expanded configuration toa fiber retaining configuration (e.g., a compressed configuration). Theshape recoverable article 121 and the fiber securement substrate 119function to anchor the optical fiber 100 against axial movement relativeto the connector body 122. Thus, when an optical connection is beingmade, optical fiber cannot be pushed from inside the connector body 122back into the fiber optic cable 112.

A fiber buckling region 190 (i.e., a fiber take-up region) is definedwithin the connector body 122 between the fiber anchoring location atthe rear of the connector body 122 and the front mating end 124 of theconnector body 122. When two connectors 69 are coupled together withinone of the adapters 64 (as shown at FIG. 19), the end faces of theferrule-less end portions 100′ of the optical fibers 100 abut oneanother thereby causing the optical fibers 100 to be forced rearwardlyinto the connector bodies 122. As the optical fibers 100 are forcedrearwardly into the connector bodies 122, the optical fibers 100buckle/bend within the fiber buckling regions 190 (see FIGS. 19, 21 and32) since the fiber anchoring location prevents the optical fiber 100from being pushed back into the optical cable 112. The fiber bucklingregions 190 are designed so that minimum bend radius requirements of theoptical fibers 100 are not violated. In one example, the fiber bucklingregions are sized to accommodate at least 0.5 millimeters or at least1.0 millimeters of rearward axial movement of the optical fibers 100. Inone embodiment, the fiber buckling regions 190 have lengths from 15-25millimeters. Fiber alignment structures 189 can be provided at the frontmating ends 124 of the connectors 69 for providing rough alignment ofthe ferrule-less end portions 100′ along insertion axes of theconnectors 69. In this way, the ferrule-less end portions 100′ arepositioned to slide into the first and second funnels 36, 38 of thealignment device 20 when the connectors 69 are inserted into a fiberoptic adapter such as one of the adapters 60, 64 or 66. When theconnector is loaded in the fiber optic adapter, the fiber bucklingregion 190 can be configured so that the optical fiber buckles generallyalong a plane (e.g., a vertical plane) that bisects the alignment slot32. In this way, the compressive load on the optical fiber does notimpart a lateral load on the fiber that could laterally displace theoptical fiber from the alignment groove 32.

Referring still to FIGS. 20 and 21, the fiber securement substrate 119can be loaded into the rear insert 130 through a front end of the rearinsert 130. A front retention structure 123 (e.g., a flange, lip, tab orother structure) of the fiber securement substrate 119 can abut, matewith, interlock with or otherwise engage a front end of the insert 130.The rear insert 130 can be press fit within the rear end of theconnector body. As used herein, the front end of the connector is themating end where the ferrule-less end portion 100′ is accessible, andthe rear end of the connector is the end where the cable is attached tothe connector body.

The shutter 74 of the fiber optic connector 69 is movable between aclosed position (see FIGS. 22 and 23) and an open position (see FIGS. 24and 25). When the shutter 74 is in the closed position, the ferrule-lessend portion 100′ of the optical fibers 100 is protected fromcontamination. When the shutter 74 is in the open position, theferrule-less end portion 100′ is exposed and capable of being accessedfor making an optical connection. The shutter 74 includes a front coverportion 75, a top portion 77 and a lever portion 79 that projectsupwardly from the top portion 77. The shutter 74 pivots between the openand closed positions about a pivot axis 73.

The fiber optic connector 69 includes a latching mechanism 200 thatpositively latches the shutter 74 in the closed position. The latchingmechanism 200 can include a latching clip 202 that engages the shutter74 to retain the shutter 74 in the closed position. As shown at FIG. 28,the latching clip 202 includes a main body 204 and two spaced-apartlatching arms 206. The main body 204 includes a base 208 and twoopposing side walls 210 that extend upwardly from the base 208. The sidewalls 210 define openings 212. The latching arms 206 have a resilient,cantilevered configuration and project forwardly from the base 208. Thelatching arms 206 include downwardly projecting release tabs 214 havingramp surfaces 216. The latching arms 206 also include end hooks 218. Theramp surfaces 216 face generally towards each other (i.e., the rampsurfaces face toward a vertical reference plane 217 (see FIG. 26) thatlongitudinally bisects the connector body 122) and are angled to extendlaterally outwardly as the ramp surfaces 216 extend in the connectorinsertion direction.

The latching clip 202 is installed on the connector 69 by snapping themain body 204 onto the connector body 122. When the main body 204 issnapped in position, the side walls 210 straddle the sides of theconnector body 122 and the base 208 is positioned beneath the undersideof the connector body 122. The side walls 210 can flex to allow sidetabs 220 of the connector body 122 to snap-fit into the openings 212 ofthe side walls 210. With the latching clip 202 is installed on theconnector body 122, the latching arms 206 extend along opposite sides ofthe connector body 122 adjacent the bottom of the connector body 122.The release tabs 214 project downwardly below the bottom side of theconnector body 122. The latching arms 206 are movable between a latchingposition (see FIG. 26) and a release position (see FIG. 27). When thelatching arms 206 are in the latching position and the shutter 74 is inthe closed position, the end hooks 218 of the latching arms 206 fitwithin receptacles 222 defined by the shutter 74 such that the latchingarms 206 retain the shutter 74 in the closed position. Thus, thelatching arms 206 prevent the shutter 74 from moving from the closedposition to the open position. When the latching arms 206 are in therelease position, the latching arms 206 are flexed laterally outwardlysuch that the end hooks 218 are outwardly displaced from the receptacles222. In this way, the latching arms 206 do not interfere with movementof the shutter 74 and the shutter 74 is free to be moved from the closedposition to the open position.

Fiber optic adapters in accordance with the principles of the presentdisclosure can include structure for consecutively moving the latchingarms 206 from the latching position to the release position and thenmoving the shutter 74 from the closed position to the open position asthe connector 69 is inserted into the fiber optic adapter. The structurecan also move the shutter 74 from the open position to the closedposition and then allow the latching arms to move from the releaseposition to the latching position as the connector 69 is withdrawn fromthe adapter. As shown at FIGS. 29, 35 and 36, the fiber optic adapter 60includes a pair of release rails 230 corresponding to each adapter port231. The release rails 230 are parallel and have ramp surfaces 232 attheir outer ends. The release rails 230 are parallel to the direction ofinsertion of the connector 69 within the adapter port 231 and the rampsurfaces 232 angle laterally outwardly as the ramp surfaces 232 extendin the connector insertion direction. The ramp surfaces 232 facegenerally away from one another and away from the central verticalreference plane 217 that longitudinally bisects the connector body 122.The fiber optic adapter 60 also includes shutter actuation posts 234corresponding to the adapter ports 231. The release rails 230 arepositioned adjacent bottom sides of the adapter ports 231 and theactuation posts 234 are positioned adjacent top sides of the adapterports 231.

When one of the connectors 69 is inserted into one of the adapter ports231, the ramp surfaces 216 of the latching arms 206 approach the rampsurfaces 232 of the release rails 230 (see FIG. 35). Continued insertionof the connector 69 into the adapter port 231 brings the ramp surfaces216, 232 into contact with one another and the ramp surfaces 216 rideover the ramp surfaces 232. As the ramp surfaces 216 ride over the rampsurface 232, the latching arms 206 are forced to flex laterallyoutwardly from the latching position of FIG. 26 to the release positionof FIG. 27. Once the ramp surfaces 216 move past the ramp surfaces 232,the release tabs 214 ride on outer sides 233 of the release rails 230 asthe connector is continued to be inserted into the adapter port 231.Thus, once the connector is inserted so that the ramp surfaces 216 ofthe latching arms 206 have moved past the ramp surfaces 232 of therelease rails 230, the outer sides 233 of the release rails 230 functionto retain/hold the latching arms 206 in the release position throughcontinued engagement with the release tabs 214.

The shutter actuation posts 234, the ramp surfaces 232 of the rails 230,the ramp surfaces 216 of the latching arms 206 and the lever portions 79of the shutters 74 are all relatively positioned such that, duringconnector insertion, the lever portion 79 of the shutter 74 contacts theshutter actuation post 234 after the ramp surfaces 216 of the latchingarms 206 have ridden over the ramp surfaces 232 of the release rails230. Thus, the relative positioning ensures that the latching arms 206have been moved to the release position prior to the lever portion 79 ofthe shutter 74 engaging the shutter actuation post 234. Contact betweenthe shutter actuation post 234 and the lever portion 79 of the shutter74 as the connector 69 is inserted into the adapter port 64 causes theshutter 74 to pivot about the pivot axis 73 from the closed position tothe open position. Since the latching arms 206 had previously been movedto the release position as described above, the latching arms 206 do notinterfere with movement of the shutter 74.

FIG. 29 shows the fiber optic adapter 60 with a left connector 69already loaded in the left adapter port 231 and a right connector 69ready to be inserted into the right connector port 231. FIG. 30 showsthe fiber optic adapter 60 of FIG. 29 with the right connector 69inserted to a position with the right adapter port 231 where the rampsurfaces 216 of the latching arms 206 are engaging the ramp surfaces 232of the release rails 230 such that the latching arms 206 have moved fromthe latching position to the release position. FIG. 31 shows the fiberoptic adapter 60 of FIG. 29 with the right connector 69 inserted to aposition within the right adapter port 231 where the latching arms 206are in the released position and the lever portion 79 of the shutter 74is contacting the shutter actuation post 234 thereby causing the shutter74 to pivot from the closed position toward the open position as theconnector 69 is inserted further into the adapter port 231. FIG. 32shows the fiber optic adapter 60 of FIG. 29 with the shutter in the openposition and the connector fully inserted into the fiber optic adapter60 such that the ferrule-less end portions 100′ of the left and rightconnectors 69 are abutting one another and are being held in co-axialalignment by the alignment device 20.

When the right connector 69 is withdrawn from the right adapter port 231of the fiber optic adapter 60, the top portion 77 of the shutter 74contacts the shutter actuation post 234 causing the shutter 74 to pivotfrom the open position to the closed position (see FIGS. 33 and 34).Thereafter, the ramp surfaces 216 of latching arms 206 slide back pastthe ramp surfaces 232 of the release rails 230. When this occurs, theinherent resiliency/elasticity of the latching arms 206 causes thelatching arms to move from the release position back to the latchingposition. Thus, the latching arms 206 are spring biased toward thelatching position. As the latching arms 206 move to the latchingposition, the end hooks 216 fit within the receptacles 222 of the closedshutter 74 thereby latching the shutter 74 in the closed position. Thus,the shutter 74 is latched in the closed position prior to fullwithdrawal of the right connector 69 from the right port 231 of thefiber optic adapter 60.

FIG. 37 shows a converter 300 in accordance with the principles of thepresent disclosure for converting the ferrule-less connector 69 to aferruled connector. In the depicted embodiment, the ferruled connectorhas a SC-type footprint/shape/profile that mates with an SC-type fiberoptic adapter 302 configured for interconnecting two ferruled SC-typeconnectors. As shown at FIGS. 38 and 39, the converter 300 includes anouter housing 304 (e.g., an SC-release sleeve that is pulled back todisengage the converter 300 from a standard SC adapter), a dust cap 306,an inner housing 308, a ferrule assembly 310 including a ferrule 311 anda ferrule hub 312 (i.e., a ferrule base) mounted to a back end of theferrule 311, the fiber alignment device 20, a spring 314 for biasing theferrule assembly 310 in a forward direction, and a retention cap 316 forsecuring the fiber alignment device 20 to the ferrule hub 312. As shownat FIG. 40, an optical fiber stub 320 is potted (e.g., adhesivelysecured) with a central bore 322 defined axially through the ferrule311. The optical fiber stub 320 has a polished end 324 positionedadjacent a front end face 326 of the ferrule 311. The dust cap 306 canbe mounted over the front end face 326 to protect the polished end 324of the optical fiber stub 320 from damage or contamination. The opticalfiber stub 320 includes a rear portion 328 that projects rearwardly froma rear end 330 of the ferrule 311. The rear portion 328 of the opticalfiber stub 320 extends through the first funnel 36 of the optical fiberalignment device 20 and is shown pressed within the fiber alignmentgroove 32 by the first ball 40.

In certain embodiments, the spring 314 can be a spring washer such as aBelleville washer or a wave washer. In this way, the spring can provideits biasing function while being relatively compact in an axialdirection.

Referring to FIGS. 39 and 40, the inner housing 308 includes a front end332 and a rear end 334. The front end 332 forms a plug interface endcompatible with a fiber optic adapter such as a standard SC adapter 302.The ferrule assembly 310 mounts with the inner housing 308 adjacent thefront end 332 of the inner housing 308. The front end face 326 of theferrule projects forwardly beyond the front end 332 of the inner housing308 so as to be accessible for connection to another fiber opticconnector. The outer housing 304 snaps over the inner housing 308 andhas a limited range of axial movement relative to the inner housing 308.When front end 332 of the inner housing 308 is inserted into the fiberoptic adapter 302, the ferrule 311 fits within an alignment sleeve ofthe fiber optic adapter 302 and latches of the adapter 302 engage upperand lower catches 338 of the inner housing 308 to lock the front end 332of the inner housing 308 within the adapter 302. To release the innerhousing 308 from the adapter 302, the outer housing 306 is retractedrelative to the inner housing 308 such that upper and lower rampsurfaces 336 of the outer housing 306 disengage the latches of theadapter 302 from the catches 338 so that the inner housing 308 can bewithdrawn from the adapter 302.

The ferrule assembly 310 and the spring 314 can be retained at the frontend 332 of the inner housing 308 by a locking clip 340. The locking clip340 can be side loaded into the inner housing 308 and captures thespring 314 and the ferrule hub 312 within the front end 332 of the innerhousing 308. For example, the ferrule hub 312 and the spring 314 arecaptured between an inner shoulder 342 of the inner housing 308 and thelocking clip 340. In this way, the spring biases the ferrule assembly310 in a forward direction. During a connection, the ferrule assembly310 can move rearwardly relative to the inner housing 308 against thebias of the spring 314 as the front end face 326 of the ferrule 311contacts the end face of the ferrule of a mating connector insertedwithin the adapter 302. The locking clip 340 is preferably lockedagainst axial movement relative to the inner housing 308. The hubassembly 310 has a range of axial movement relative to the inner housing308 that is defined between the inner shoulder 342 and the locking clip340. The alignment device 20 is mounted to the hub assembly 310. Thus,the alignment device 20 is carried with the hub assembly 310 as the hubassembly 310 moves axially relative to the inner housing 308. In oneexample, at least a portion of the alignment device fits inside aportion of the ferrule hub 312. For example, the ferrule hub 312 candefine a receptacle 344 that receives one end of the alignment device20. The retention cap 316 can snap-fit to a back end of the ferrule hub312 and is configured to attach the alignment device 20 to the ferrulehub 312.

By mounting the alignment device 20 within the ferrule hub 312, theassembly can be relatively short in length. This can be significantbecause limited space is available. In another example, the assembly canbe further shortened by mounting at least a portion of the alignmentdevice 20 within the ferrule 311. For example, FIG. 42 shows the ferrule311 modified to include a rear receptacle 346 for receiving a portion ofthe alignment device 20 thereby shortening the overall length of theassembly.

In use, the connector 69 is inserted into the converter 300 through therear end 334 of the inner housing 308. When inserted within the innerhousing 308, the ferrule-less end portion 100′ of the optical fiber 100of the connector 69 slides inside the alignment device 20 and isco-axially aligned with and optically connected to the optical fiberstub 320 supported by the ferrule 311. The ferrule-less end portion 100′can extend through the second funnel 38 of the alignment structure 20and can be pressed into the alignment groove 32 by the ball 41. Theinner housing 308 can include structure for retaining the connector 69within the rear end 334. For example, the inner housing 308 can includea catch 350 that engages the latch 70 of the connector 69. The latch 70is connected to the main body 122 of the connector 69 by an interconnectpiece 352. When the connector 69 is latched in the inner housing 308,the catch 350 opposes a latching surface 351 of the latch 70 and therear end 334 opposes the interconnect piece 352 to limit axial movementbetween the connector 69 and the inner housing 308 in both inner andouter axial directions. By depressing a rear end 354 of the latch 70,the latching surface 351 can be disengaged from the catch 350 to permitremoval of the connector 69. Contact between the rear end 334 of theinner housing 308 and the interconnect piece 352 limits the distance theconnector 69 can be inserted into the inner housing 308. It will beappreciated that the inner housing 308 also includes structure for: a)moving the latching arms 206 of the connector 69 from the latchingposition to the release position; and b) moving the shutter 74 of theconnector 69 from the closed position to the open position. For example,as disclosed with regard to the fiber optic adapter 60, the innerhousing 308 can include the release rails 230 and the shutter actuationpost 234.

FIGS. 43-53 illustrate another optical fiber alignment device 420 inaccordance with the principles of the present disclosure. Referring toFIG. 52, the optical fiber alignment device includes an alignmenthousing 424 including first and second ends 426, 428. A fiber insertionaxis 422 extends through the alignment housing 424 between the first andsecond ends 426, 428. The alignment housing 424 has a main body 429 thatis elongated between the first and second ends 426, 428 and thatincludes an outer shape 431 that is cylindrical. The alignment housing424 also includes a longitudinal rib 430 that projects laterallyoutwardly from the outer shape 431 of the main body 429 of the alignmenthousing 424.

The alignment housing 424 defines an internal chamber 432 (see FIGS.51-53). The internal chamber 432 extends completely through the lengthof the alignment housing 424 from the first end 426 to the second end428. In this way, optical fibers can be inserted along the fiberinsertion axis 422 through the alignment housing 424. The internalchamber 432 includes an elongated access slot 434 having a length L1(See FIG. 51), a depth D1 (see FIG. 51) and a width W1 (see FIG. 53).The length L1 extends along the length of the alignment housing 424. Thedepth D1 extends laterally (i.e., radially) into the alignment housing424. The width W1 is transverse with respect to the depth D1 and thelength L1. The internal chamber 432 also includes first and secondball-receiving pockets 436, 438 positioned along the length L1 of theelongated access slot 434. The first and second ball-receiving pockets436, 438 each have a width W2 (see FIG. 53) that is larger than thewidth W1 of the elongated access slot 434. The first and secondball-receiving pockets 436,438 have depths D2 (see FIG. 53) that areparallel to the depth D1 of the elongated access slot 434. The first andsecond ball-receiving pockets 436,438 each include cylindricalpocket-defining surfaces 440 (see FIG. 52) that extend partially aroundball insertion axes 442 (see FIG. 51) that are parallel to the depthsD2. The pocket-defining surfaces 440 of each of the pockets 436,438 arepositioned on opposite sides of the elongated access slot 434. Thepocket-defining surfaces 440 of the first ball-receiving pocket 436oppose one another, and the pocket-defining surfaces 440 of the secondball-receiving pocket 438 oppose one another. The first and secondball-receiving pockets 436, 438 also include ball seats 444 positionedat opposite sides of the elongated access slot 434. It will beappreciated that one ball seat 444 corresponds to each of thepocket-defining surfaces 440. The ball-seats are located at bottom endsof the first and second ball-receiving pockets 436, 438.

The internal chamber 432 also includes a rod receiving region 450 at thebottom of the depth D1 of the elongated access slot 434. Therod-receiving region 450 has a width W3 that is larger than the width W1of the elongated access slot 434. The rod receiving region 450 extendsgenerally along the entire length of the alignment housing 424.

The optical fiber alignment device 420 also includes first and secondalignment rods 452, 454 (see FIG. 52) that fit within the rod-receivingregion 450 of the alignment housing 424. The first and second alignmentrods 452,454 mount parallel to one another within the rod-receivingregion 450 and can be inserted into the rod-receiving region 450 throughthe elongated access slot 434. Each of the first and second alignmentrods 452 includes an intermediate section 456 that is generallycylindrical in shape. Each of the first and second alignment rods 452also has rounded ends 458. In the depicted embodiment, the rounded ends458 are spherical in shape and form semi-spheres. The intermediatesections 456 of the first and second alignment rods 452, 454 cooperateto define a fiber alignment slot 460 that extends along the fiberinsertion axis 422 through the alignment housing 424. The rounded ends458 are positioned adjacent the first and second ends 426, 428 of thealignment housing 424. The alignment housing 424 defines partial funnelstructures 462 positioned at the first and second ends 426, 428. Thepartial funnel structures 462 are positioned above the rounded ends 458of the first and second alignment rods 452, 454. The partial funnelstructures 462 form a tapered, transition that angles toward the fiberinsertion axis 422 and the fiber alignment slot 460. The partial funnelstructures 462 cooperate with the rounded ends 458 of the first andsecond alignment rods 454, 456 to define a tapered lead-in structure forguiding optical fibers toward the fiber insertion axis 422.

Similar to the fiber optic alignment device 20, the optical fiberalignment device 420 is configured for optically aligning the ends oftwo optical fibers desired to be mechanically and optically connectedtogether. The optical fiber alignment device 420 further includesstructure for urging the optical fibers desired to be opticallyconnected together into contact with the fiber alignment slot 460defined by the fiber alignment rods 452, 454. In the depictedembodiment, the fiber optical alignment device 420 includes first andsecond balls 470, 471 (i.e., fiber contact members) positionedrespectively within the first and second ball-receiving pockets 436,438. The balls 470, 471 are depicted as being spherical in shape. Wheninserted within their corresponding first and second ball-receivingpockets 436, 438, the first and second balls 470, 471 seat against theball seats 444. Lower portions of the first and second balls 470, 471extend downwardly into the rod-receiving region 450 and are alignedalong the fiber alignment slot 460 and the fiber insertion axis 422. Thepocket defining surfaces 440 surround portions of the balls 470,471 andmaintain alignment of the balls 470, 471 with their respective ballinsertion axes 442. In certain embodiments, the ball insertion axes 442intersect the fiber insertion access 422 and the fiber alignment slot460.

The optical fiber alignment device 420 further includes a biasingarrangement for urging the balls 470, 471 generally toward the fiberalignment slot 460. For example, the biasing arrangement can urge theballs 470, 471 in a direction transverse with respect to the fiberinsertion axis 422. In the depicted embodiment, the biasing arrangementis shown including a clip 472 (e.g., a metal clip having elasticproperties) mounted (e.g., snap fitted) over the main body 429 of thealignment housing 424. The clip 472 can have a transversecross-sectional profile that is generally C-shaped. Ends 474 of the clipcan abut against sides of the longitudinal rib 430 of the alignmenthousing 424. When the clip 472 is snapped or otherwise fitted over thealignment housing 424, the clip 472 functions to capture the first andsecond balls 470, 471 within their respective first and secondball-receiving pockets 436, 438. The clip 472 can include biasingstructures such as first and second springs 476, 478 for respectivelybiasing the balls 470, 471 toward the fiber alignment slot 460. Asdepicted, the first and second springs 476, 478 are leaf springs havinga cantilevered configuration with a base end integrally formed with amain body of the clip 472 and free ends that are not connected to themain body of the clip 472. In the depicted embodiment, the first andsecond springs 472, 474 both extend from their base ends to their freeends in the same rotational direction about the fiber insertion axis422. The springs 476, 478 are defined by cutting or slitting the mainbody of the clip 472 so as to define slots in the main body of the clip472 that surround three sides of each of the springs 476, 478.

In use of the optical fiber alignment device 420, two optical fibersdesired to be optically connected together are inserted into the firstand second ends 426, 428 of the alignment housing 424. As the opticalfibers are inserted into the first and second ends 426, 428, the partialformal structure 426 combined with the rounded ends 458 of the first andsecond alignment rods 452, 454 cooperate to guide the ends of theoptical fiber toward the fiber insertion axis 422. Continued insertionof the optical fibers causes the optical fibers to move along the fiberalignment slot 460 defined by the intermediate sections 456 of the firstand second alignment rods 452, 454. As the optic fibers move along thefiber alignment slot 460, the optical fibers force their correspondingballs 470, 471 away from the fiber alignment slot 460 against the biasof the springs 476, 478. The optical fibers slide along the fiberalignment slot 460 until the end faces of the optical fibers areoptically coupled to one another. In this configuration, the first andsecond spring 476, 478 and the first and second balls 470, 471 functionto clamp or otherwise retain the optical fibers in the optically coupledorientation within the fiber alignment slot 460. In this way, theoptical fibers are pressed within the fiber alignment slot 460 by thefirst and second balls 470, 471 such that axial alignment between theoptical fibers is maintained.

What is claimed is:
 1. A fiber optic apparatus comprising: a ferrule assembly including a ferrule and a ferrule hub mounted to the ferrule adjacent a rear end of the ferrule, the ferrule assembly also including an optical fiber stub potted in the ferrule, the optical fiber stub having a rear portion that projects rearwardly from the rear end of the ferrule; and an optical fiber alignment device carried with the ferrule assembly and positioned at least partially within the ferrule hub, the optical fiber alignment device defining a fiber insertion axis, the optical fiber alignment device including an alignment groove, the rear portion of the optical fiber stub being aligned along the fiber insertion axis and extending within the alignment groove, the rear portion of the optical fiber stub being spring biased into the alignment groove from an open side of the alignment groove.
 2. The fiber optic apparatus of claim 1, further comprising a spring that biases the ferrule assembly in a forward direction.
 3. The fiber optic apparatus of claim 2, wherein the spring includes a spring washer.
 4. The fiber optic apparatus of claim 1, wherein the ferrule defines a receptacle for receiving at least an end portion of the optical fiber alignment device.
 5. The fiber optic apparatus of claim 1, further comprising a retention cap configured to snap-fit to a back end of the ferrule hub.
 6. The fiber optic apparatus of claim 5, wherein the retention cap is configured to attach the optical fiber alignment device to the ferrule hub.
 7. The fiber optic apparatus of claim 1, wherein the optical fiber alignment device includes at least one biasing structure that is spring biased toward the fiber insertion axis.
 8. The fiber optic apparatus of claim 7, wherein the at least one biasing structure is configured to clamp the rear portion of the optical fiber stub.
 9. A fiber optic apparatus comprising: a ferrule assembly including a ferrule and a ferrule hub mounted to the ferrule adjacent a rear end of the ferrule, the ferrule assembly also including an optical fiber stub potted in the ferrule, the optical fiber stub having a rear portion that projects rearwardly from the rear end of the ferrule; and an optical fiber alignment device carried with the ferrule assembly and positioned at least partially in the rear end of the ferrule, the optical fiber alignment device defining a fiber insertion axis, the optical fiber alignment device including an alignment groove, the rear portion of the optical fiber stub being aligned along the fiber insertion axis and extending within the alignment groove, the rear portion of the optical fiber stub being spring biased into the alignment groove from an open side of the alignment groove.
 10. The fiber optic apparatus of claim 9, further comprising a spring that biases the ferrule assembly in a forward direction.
 11. The fiber optic apparatus of claim 10, wherein the spring includes a spring washer.
 12. The fiber optic apparatus of claim 11, wherein at least a portion of the optical fiber alignment device is positioned in a rear receptacle defined in the ferrule.
 13. The fiber optic apparatus of claim 9, further comprising a retention cap configured to snap-fit to a back end of the ferrule hub.
 14. The fiber optic apparatus of claim 13, wherein the retention cap is configured to attach the optical fiber alignment device to the ferrule hub.
 15. The fiber optic apparatus of claim 9, wherein the optical fiber alignment device includes at least one biasing structure that is spring biased toward the fiber insertion axis.
 16. The fiber optic apparatus of claim 15, wherein the at least one biasing structure is configured to clamp the rear portion of the optical fiber stub. 